Lung Deposition of Fenoterol and Flunisolide Delivered Using a Novel Device for Inhaled Medicines: Results

Lung Deposition of Fenoterol and Flunisolide Delivered Using a Novel Device for Inhaled Medicines: ResultsSubjects
As shown in Table 1, the demographic characteristics of the patients in both studies were similar. A total of 12 subjects (5 male, 7 female), with a mean age of 27.4 years and normal lung function (mean FEV1, 106% predicted), completed the fenoterol study, whereas 12 subjects (6 male, 6 female), with a mean age of 27.3 years and a mean FEV1 of 97% predicted completed the flunisolide study. buy zyrtec online

The mean parameters of inhalation for the two studies given in Table 2 show that subjects inhaled slowly at a rate between 25 and 35 L/min and had a breath-holding pause of approximately 10 s.
Whole Lung Deposition
Whole lung deposition of fenoterol was significantly greater when delivered by the RESPIMAT (mean, 39.2%) compared with the MDI (mean, 11.0%; p<0.01) and MDI with Aerochamber (mean, 9.9%; p<0.01) as shown in Table 3 and Figure 2 (top, a). There was no significant difference in the mean whole lung deposition of fenoterol between the MDI and MDI with Aerochamber. Similarly, the whole lung deposition of flunisolide delivered by the RESPIMAT device (mean, 44.6%) was significantly greater than that delivered by either the RESPIMAT with baffle (mean, 29.5%; p<0.01) or the MDI with spacer (mean, 26.4%; p<0.01) as shown in Table 4 and Figure 2 (bottom, b). However, the difference in mean whole lung deposition of flunisolide between the RESPIMAT with baffle and the MDI with spacer was not significant.
Regional Lung Deposition
The RESPIMAT deposited a greater percentage of the fenoterol dose in the central, intermediate, and peripheral lung regions than either the MDI or the MDI with Aerochamber (Table 3). The mean penetration indexes for the three regions lay between 1.3 and 1.5, and this parameter was significantly higher for the MDI with Aerochamber than for the RESPIMAT (p<0.05; Table 3).
Comparison of the regional deposition of flunisolide demonstrated that the RESPIMAT deposited a greater percentage of the dose in the central, intermediate, and was similar for the RESPIMAT with baffle and MDI with spacer, the RESPIMAT with baffle deposited a significantly greater percentage of the dose in the peripheral region of the lungs than the MDI with spacer (p<0.05). This was reflected in a significantly higher penetration index for the RESPIMAT with baffle compared with the MDI with spacer (p=0.02) as shown in Table 4.
Table 2—Inhalation Details

Duration of Inhalation, s Inhaled Volume, L Inhalation Rate, L/min Breath-holding Pause, s
Fenoterol study
RESPIMAT 6.7 (2.5) 2.6 (1.3) 24.8(10.2) 10.7 (0.9)
MDIf 5.8 (1.3) 2.6 (1.2) 27.2(10.4) 10.3 (1.6)
MDI with Aerochamber 5.9 (2.4) 2.7 (0.8) 30.5 (13,5) 10.8 (1.0)
Flunisolide study
RESPIMAT 5.4 (3.3) 2.4 (1.7) 29.8 (14.7) 10.1 (1.3)
RESPIMAT+baffle 6.0 (3.5) 2.4 (1.0) 27.4 (10.4) 9.7 (1.2)
MDI with spacer* 5.4 (4.5) 2.5 (1.2) 35.0 (20.1) 10.6(1.1)

Table 3—Percentage Distribution of Metered Dose of Fenoterol in Lungs, Oropharynx, and Recovered From the Dosing Apparatus and Exhaled Air

RESPIMAT MDI MDI With Aerochamber
Whole lung, % 39.2 (12.7) 11.0 (4.9) 9.9 (3.4)
Central lung zone, % 11.0 (3.7)« 3.1 (1.1) 2.5 (0.9)
Intermediate lung zone, % 14.1 (4.9) 3.7 (1.8) 3.6 (1.2)
Peripheral lung zone, % 14.1 (4.8) 4.2 (2.1) 3.8 (1.5)
Oropharynx, % 37.1 (10.4) 71.7 (7.4)” 3.6 (2.4)
Dosing apparatus, 21.9 (6.1) 16.7 (5.4) 86.2 (5.2)
Exhaled air, % 1.9 (1.7)*” 0.6 (0.4)** 0.4 (0.3)
Penetration index 1.3 (0.4) 1.4 (0.4) 1.5 (0.4)tf

Table 4—Percentage Distribution of Flunisolide in Lungs, Oropharynx9 and Recovered From the Dosing Apparatus and Exhaled Air

RESPIMAT RESPIMAT(Baffle) MDI With Spacer
Whole lung, % 44.6 (7.9) 29.5 (4.4) 26.4 (6.2)
Central lung zone, % 10.9 (1.9) 7.0 (1.4) 7.4 (2.0)
Intermediate lung 15.8 (2.4) 10.4 (1.6) 9.2 (2.1)
zone, %
Peripheral lung zone,% 17.9 (4.2)” 12.1 (2.2) 9.8 (2.6)
Oropharynx, % 26.2 (6.8)§ 7.8 (2.5)” 31.2 (9.6)
Dosing apparatus, %* Exhaled air, %’ 16.7 (4.1)*® 55.4 (7.3)” 42.0 (8.8)
12.4 (8.3) 7.4 (6.0) 0.4 (0.2)
Penetration index 1.6 (0.3) 1.8 (0.4)# 1.4 (0.5)

 

Figure 2. Whole lung deposition of (top, a) fenoterol and (bottom, b) flunisolide in individual subjects. Solid bar represents mean values.

Figure 2. Whole lung deposition of (top, a) fenoterol and (bottom, b) flunisolide in individual subjects. Solid bar represents mean values.

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